Volunteers have been exposed to the coronavirus by covid-19 as part of a clinical study.
koto_feja/GETTY
Deliberately exposing other people to the coronavirus that causes Covid-19 as part of a so-called risk study helped us understand why some people seem immune to infection.
In the first study of its kind on COVID-19, conducted in 2021, a group of foreign researchers evaluated 16 other people with no known health conditions who had not tested positive for the SARS-CoV-2 virus or been vaccinated against it. .
Learn More
How to Tell if Your Immune Formula Is Strong or Strong
The. . .